Blue, blue and blue: why malignant Neptune urgently deserves more attention

If NASA adopts the recommendation of the scientific community in the coming years and Sends a spacecraft to Uranus, Neptune will become the only planet that humanity has not visited during a special mission. That’s a shame, because Neptune boasts interesting mysteries. And the planet has a moon with Triton where life can be found.

We don’t hear much about Neptune. Certainly not so much as on other planets. Space robots regularly take snapshots of the surface of Mars and the clouds of Jupiter. Mercury is a frequent scapegoat for people interested in astrology. For 13 years, the Cassini spacecraft has orbited Saturn and made an impressive series of observations there. Planetary scientists recently announced that NASA should prioritize sending a probe to Uranus within the next decade. Neptune’s brief foray into the news cycle last week, Because of a new study on what makes Neptune so blueIt was a rare event.

Even this discovery was an accident. Astronomers were out to study the atmospheres of both Neptune and Uranus, not to investigate the specific mystery of Neptune’s beautiful appearance. The ice giants Uranus and Neptune — so named because scientists believe the planets originally fused together from icy material — are often studied this way: as a pair. They have a lot in common. It’s about the same size: larger than Earth, but smaller than Jupiter and Saturn. They are surfaceless worlds, with atmospheres of hydrogen and helium and a dash of methane. Scientists suspect that the pressure inside is so intense that carbon atoms squeeze the diamond.

Neptune has always been a little weird

Scientists already knew that Neptune and Uranus get their overall bluish appearance from methane in their atmosphere, which absorbs the red hues of incoming sunlight, leaving blue-green before our eyes. But now it has been discovered that a certain layer of the methane nebula on Uranus is twice as thick as on Neptune.

Researchers believe that Neptune, which has a more turbulent atmosphere, is better at shaking methane molecules and thinning this layer. Therefore, Uranus is soft aquamarine He is Neptune Cerulean bluethe bluest planet in our solar system.

Neptune has always been a little weird. Astronomers didn’t realize Neptune was there until they noticed the discovery of Uranus through their telescope in 1781, being dragged into its orbit by the gravitational pull of an invisible celestial body. Neptune was finally discovered in 1846, exactly where astronomers expected.

Voyager 2 and The Great Dark Spot

After many years and technological leaps then, in 1989, NASA’s Voyager 2 spacecraft passed by, the last stop on a big tour of the exoplanets. The flyby gave us a close-up look at a glorious blue world, mane and its rings. (Yes, Neptune has rings! They’re not as flashy as Saturn’s rings, but they’re there, made of tiny bits of rock and dust.) Voyager picked up bruises deep in the atmosphere that turned out to be powerful storms, and scientists called it the largest—Earth-sized—spot they’ve seen great dark.

Since then, no spacecraft has visited Neptune. or Uranus. Planetary scientists decided in their latest recommendation to NASA that Uranus should be visited simply because Uranus is closer and it will take less time to get to it. That’s the challenge of exploring worlds that take a long time to revolve around the sun – 84 years for Uranus and 165 colossal years for Neptune.

A mission dedicated to Uranus, departing sometime in the early 2030s, will undoubtedly enrich our understanding of both ice giants. But that doesn’t really give Neptune what the planet deserves. After all, there are many things to investigate.

Neptune gets cold when the planet should be warming and nobody has a clue why

For example: Neptune has a great deal of residual internal heat from its formation, which the planet is currently radiating into space. Neptune emits 2.5 times as much heat as the planet absorbs from the sun, while Uranus, despite its proximity to the sun, does not. Which is very strange, because the ice giants are very similar in composition. All this excess makes Neptune a windy place. (Jupiter may have the most beautiful storms in the solar system, but Neptune has the fastest winds.) Scientists are eager to understand how Neptune’s weather works.

Have you found Voyager 2’s big dark spot? It had completely disappeared by the time the Hubble Space Telescope spotted the planet in the 1990s. Other dark spots appeared and went the same way.

Also strange: seasonal temperatures for Neptune. It’s currently summer in the planet’s southern hemisphere, and it has been for nearly two decades. (On Neptune, each season lasts about 40 years.) So when planetary scientists recently examined telescope observations at the time, they expected to see signs that the planet was steadily warming. But Neptune is cooling instead. Nobody has any idea why.

Triton: a promising candidate for extraterrestrial life

Neptune also has one of the most interesting moons in the solar system: Triton, a planet-sized world with a smooth, icy surface. When Voyager 2 passed through the Neptune system, it detected plumes of nitrogen gas emanating from cracks in the lunar terrain. Scientists believe that an entire ocean is emerging under the frozen crust of Triton, making it a potentially promising candidate in the search for extraterrestrial life.

NASA recently considered a mission concept for a special probe for Triton, but the space agency decided to fund two spacecraft to Venus instead. Will we go to Neptune again? Not with astronauts, of course, but with a specially designed spacecraft to explore the wonders of our eighth planet? The world’s newest space observatory, the James Webb Space Telescope, will begin observing the ice giant later this year and should provide unprecedented data on the nature of its atmosphere. But that doesn’t mean you’re there. At this scale, we don’t know Neptune at all, and we won’t know it for some time.

A recent mission concept for Neptune suggested a launch in 2033 and arrive in 2049. But moving to the start would mean moving that timeline by a decade, and possibly longer. So the bluer planet may have to wait well until 2050 to visit.

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